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The space groups of 98 structures originally reported in Cc are revised. In 75 cases the revised space group is C2/c and the revision entails adding a center of symmetry, usually leading to large changes in bond lengths and angles. In the remaining 23 cases, where the revised space group is Fdd2, R3c or (in one case) I
c2, the lattice type is changed but no center is added; in these cases the molecular dimensions are effectively unchanged.
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